Answer :
Final answer:
To find the speed after the first 4 seconds, we first convert the final speed to m/s and calculate the constant acceleration. Then we apply it for the 4-second duration, resulting in a speed of 13.9 m/s after 4 seconds.
Explanation:
The question is asking for the speed of a product (implied to be some kind of vehicle) after accelerating for 4 seconds from rest to a speed of 100 km/hr over 8 seconds. This is a physics problem involving constant acceleration. First, we need to convert the final speed from km/hr to m/s by multiplying by ⅟₉₀ or ₁ₙ₀₀ₐ₀ to get an equivalent of 27.8 m/s over 8 seconds. Now that we have the speed in m/s, we use the formula for constant acceleration (final velocity = initial velocity + acceleration × time). Here the initial velocity is 0 m/s, and the final velocity is 27.8 m/s at 8 seconds. We calculate the acceleration using ₂⁷₈ m/s divided by ₈ s, which gives an acceleration of 3.475 m/s². To find the speed after 4 seconds, we multiply the acceleration by 4 seconds, resulting in a speed of 13.9 m/s, which is option b.
